I don't see markings on the fiberglass shell itself (only on the top of the lamp holder). The liner has deteriorated, the material has split and cracked and is chipping/flaking off as shown. I put Skullgard in the title but it is not marked as such.
eBay
The MSA 48733 hard hat lug is designed for MSA Skullgard Non-Slotted hats. Compatible with MSA Skullgard Non-Slotted hats. Hard Hat Compatibility : MSA Skullgard Non-Slotted Hat. Minimum Order Quantity : 1.
eBay
Not sure where this is exactly from, probably Ohio. Shows wear, see pics.
eBay
The AO Safety White Construction Hard Hat Helmet XLR8 Adjustable is a high-quality protective gear designed for use in various construction and mining settings. Made by the reputable brand Skullgard, this hard hat comes in a stylish copper/bronze color. With its adjustable features, it offers a comfortable fit for long wearing periods while providing the necessary protection for workers in hazardous environments. This helmet is a reliable choice for ensuring safety on job sites in the United States.
eBay
MSA 816651 Skullgard Cap Style Safety Hard Hat with Swing Ratchet Suspension | Non-slotted Cap, Made of Phenolic Resin, Radiant Heat Loads up to 350F - Standard Size in Tan.
eBay
MSA 454617 Skullgard Cap Style Safety Hard Hat with Staz-on Pinlock Suspension | Non-slotted Cap, Made of Phenolic Resin, Radiant Heat Loads up to 350F - Standard Size in Natural Tan.
eBay
Manufactured by MSA, this component is known for its durability and ease of use. Model : 10126692. This suspension system is designed to provide comfort and security. It is easy to adjust, even while wearing gloves.
eBay
11-1/8” from back to tip of brim 8-1/8” across bottom rim center left to right, 5.5” tall Very good condition with some minor scratches etc. see all photos
eBay